Telephone/Transcript
Transcript T''ext reads: The Mysteries of Life with Tim and Moby'' Moby is lying in bed with a dog while talking on the phone to Crusher who is also lying in bed. MOBY: Beep. CRUSHER: Beep. MOBY: Beep. The door opens and Tim is behind it. TIM: Hey, could you get off the phone for one second? I'm expecting a call. Moby blows a gum bubble. TIM: I didn't know you had a dog. Moby's bubble pops. Tim catches a letter that pops out of Moby's popped gum bubble. Tim reads from the typed letter. TIM: Dear Tim and Moby, How does a telephone work? From, Theodore. TIM: You picked the right people to ask about telephones; sometimes I think Moby is glued to his. The telephone is actually a pretty simple gadget. Basically, it changes sound waves into electricity, and then back into sound waves. Moby's using an old-style telephone with something called a hook switch. When the handset is holding the switch down, the phone's circuit is open, and no electricity flows through it. T''im holds down the hook switch.'' MOBY: Beep. Moby glares angrily at Tim, who has just disconnected his call. TIM: Oh, sorry. Sorry. When you lift the handset, it releases a spring below the switch. An inset shows the spring and circuit inside the phone's switch. TIM: That completes the circuit between the phone and the wall jack, the connection where the phone plugs in. An animation shows a phone wire plugging into a wall jack. TIM: Cordless phones have switches too, but most of them work a little differently. They use electronic switches that turn on when you press the talk button or remove the handset from the base. An animation shows someone taking a cordless phone out of its base and pressing the phone's talk button. TIM: Cordless phones need a separate power cord to charge the handset's battery. An image shows the base plugged into a wall socket with a power cord. TIM: But old-style phones get all the juice they need from the wall jack. MOBY: Beep. TIM: The wall jack is connected by wire to a telephone box near your home. An animation shows the connection between a wall jack and a telephone box on a telephone poll. TIM: That box, and every other box in your town or county, is connected to a station called the local exchange. An image shows telephone wires and boxes that connect to a local exchange.TIM: The local exchange directs calls where they need to go. When the exchange is ready to handle your call, it sends a small electric signal to your phone, and you hear a dial tone. Tim lifts the phone to his ear and hears a dial tone. MOBY: Beep. TIM: Of course, all that happens in a split second after you pick up the handset! Moby dials the phone.MOBY: Beep. TIM: Each button on your phone's keypad sends its own unique signal to the exchange. The combination of unique signals, the phone number, tells the local exchange where to route your call. Then the signal travels through a series of main and local exchanges until it reaches the person you're calling. Tim holds the handset and the robot Crusher answers the phone. CRUSHER: Beep. TIM: Or the robot, for that matter. The microphone in the mouthpiece turns the sound of my voice into an electric signal. CRUSHER: Beep. TIM: If you're using a cordless phone, like Crusher, the handset transmits your voice to the base station as an FM radio signal. The radio waves from Crusher's phone are shown going to the base.TIM: The base station converts the radio signals into electricity, and sends it into the wall jack. The electricity going through the base's wire to the wall jack is shown. TIM: Meanwhile, the base station transmits signals from my phone to Crusher's handset. The signals are shown going from the phone's base to Crusher's handset.TIM: And the speaker in his earpiece turns those signals back into sound waves. Sound waves coming from Crusher's phone's earpiece is shown. CRUSHER: Beep. TIM: Crusher's handset and base station use different FM frequencies to transmit their signals. That lets him send and receive signals at the same time! Different simultaneous sound waves to and from the handset and base station are shown. TIM: La la la la la la la la la la la! CRUSHER: Beep. Beep. Beep. Side by side images show Tim and Crusher talking into their phones' handsets. Crusher gets mad and slams his phone into the base, which breaks in half.TIM: Meanwhile, a device called a duplex coil blocks the sound of your own voice coming back at you through the earpiece. MOBY: Beep.TIM: Good point: Older cordless sets work on the 900 megahertz frequency, while newer ones work on higher frequencies. An image shows a 900 megahertz phone, then 2,000 and 2,400 megahertz phones next to it.TIM: None of these frequencies are better than the others. But manufacturers need to change them because so many wireless gadgets share the same frequencies. From baby monitors to cell phones to WiFi networks, older frequencies are getting more and more crowded, like a wireless traffic jam. Images show these gadgets sending and receiving waves.TIM: So every time one frequency gets overused, cordless phones switch to a new one that's less crowded. An animation shows phones with 900, 2,000, and 2,400 megahertz knocked out of the way and replaced with one running at 8.7 gigahertz. TIM: And there you have it, that's our movie on– TIM: Who is it? Crusher walks into Moby's bedroom. Crusher grabs the handset from Moby and smashes it into the base, destroying the phone. He then eats the handset in one bite. The dog jumps up and barks.MOBY: Beep. Beep. Beep. Beep. Moby waves his arms, beeping angrily at Crusher. CRUSHER: Beep. Beep. Beep. Beep. TIM: All right, well. I'll just, I'll just leave and let you two work this out. Moby and Crusher continue to beep angrily while the dog continues to bark. 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